The number of refugees from the conflict in Ukraine has risen to 2,8 million, says the UN.

Reuters - People fleeing the relative safety of western Ukraine joined thousands crossing into eastern Europe on Monday (14), after Russia attacked a Ukrainian base near the border with NATO member Poland.

Ukraine said 35 people were killed at the base on Sunday. Moscow said up to 180 "foreign mercenaries" died and a large number of foreign weapons were destroyed.

Ukraine also reported new airstrikes at an airport in the west of the country. 

The number of refugees fleeing Ukraine since the Russian invasion on February 24 has risen to more than 2,8 million, UN data showed on Monday, in what has become the fastest-growing refugee crisis in Europe since World War II.

European Union authorities said that 5 million people could end up fleeing, while others have increased the number.

Millions of people were also displaced within Ukraine, with many evacuated only to the quieter regions of the west, including cities like Lviv. 

Myroslava, 52, had fled her home in the Ternopil region of western Ukraine and was waiting at a train station terminal in Krakow, Poland, to be picked up by acquaintances. She didn't know where she would be staying.

"We left because of yesterday's attack," she said, adding that she had hoped western Ukraine would be safe. "We weren't planning on leaving, but since it was so close, we decided to."

Polish Prime Minister Mateusz Morawiecki said in a press conference with his Ukrainian and Lithuanian counterparts that the attack near their border showed that Russia wanted to "create panic among the civilian population." 

Diplomatic boost

Fighting continued in many of Ukraine's major cities, including the capital Kyiv. Ukraine said it would attempt to evacuate civilians through 10 humanitarian corridors on Monday. 

Russia denies attacking civilians, describing its actions as a "special operation" to demilitarize and "denazify" Ukraine. Ukraine and its Western allies call this a baseless pretext for the Russian invasion of the democratic country of 44 million inhabitants.

"Houses were blown up," said Alena Kasinyska, a refugee from the southern Ukrainian city of Mykolaiv, after crossing into Romania at Isaccea, a busy border crossing in the Danube Delta. "People have nowhere to live, we are afraid."

Ukraine said it began "tough" negotiations with Russia on Monday regarding a ceasefire, immediate troop withdrawal, and security guarantees.

Both sides reported little progress over the weekend, after previous rounds focused mainly on ceasefires to bring aid to cities besieged by Russian forces and evacuate civilians. These truces frequently failed.

Authorities and volunteers across Central and Eastern Europe are struggling to provide food, shelter, and medical assistance to the millions of refugees crossing their borders.

Frontline states, such as Poland, which received well over half of the total number of refugees, and Slovakia, Romania, Hungary, and Moldova, took in the vast majority of refugees, some of whom then moved westward.

Poland's border guard said that around 1,76 million people have entered the country since the start of the fighting, with 18.400 arriving during the early hours of Monday.

"We estimate that more than 1 million Ukrainians remain in Poland and we must do everything to ensure their safety," Polish Deputy Minister of Internal Affairs Pawel Szefernaker told the private television channel TVN24.

Sympathy for the plight of their neighbors and deep memories of Moscow's rule saw a surge of volunteer efforts, but the scale of the refugee crisis heightened fears of being overwhelmed.

Some countries further from Ukraine's borders, such as the Czech Republic, have also received tens of thousands of refugees, putting pressure on local authorities, while others, such as Lithuania, have only just begun to receive significant numbers.

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